/**
 * A concrete state for customer shopping
 */

import java.io.*;

public class Pay extends ShopState {
    public static boolean instanceFlag = false; //true if have 1 instance

    private Pay() {
    }

    public static Pay getInstance() {
        if (!instanceFlag) {
            instanceFlag = true;
            return new Pay();
        }
        return null;
    }

    public void pay() {
        System.out.println("The state is pay now !");
    }
}